The Solar Upper Transition Region Imager (SUTRI) Onboard the SATech-01 Satellite

Abstract

The Solar Upper Transition Region Imager (SUTRI) onboard the Space Advanced Technology demonstration satellite (SATech-01), which was launched to a sun-synchronous orbit at a height of $\sim$500 km in July 2022, aims to test the on-orbit performance of our newly developed Sc/Si multi-layer reflecting mirror and the 2k$\times$2k EUV CMOS imaging camera and to take full-disk solar images at the Ne VII 46.5 nm spectral line with a filter width of $\sim$3 nm. SUTRI employs a Ritchey-Chrétien optical system with an aperture of 18 cm. The on-orbit observations show that SUTRI images have a field of view of $\sim$ 41.6’$\times$41.6’ and a moderate spatial resolution of $\sim$8” without an image stabilization system. The normal cadence of SUTRI images is 30 s and the solar observation time is about 16 hours each day because the earth eclipse time accounts for about 1/3 of SATech-01’s orbit period. Approximately 15 GB data is acquired each day and made available online after processing. SUTRI images are valuable as the Ne VII 46.5 nm line is formed at a temperature regime of $\sim$0.5 MK in the solar atmosphere, which has rarely been sampled by existing solar imagers. SUTRI observations will establish connections between structures in the lower solar atmosphere and corona, and advance our understanding of various types of solar activity such as flares, filament eruptions, coronal jets and coronal mass ejections.

Partial Eruption of Solar Filaments. I. Configuration and Formation of Double-decker Filaments

“…The filament partial eruption event of interest occurred in NOAA AR 13176 on 2022 December 30 and was well observed by CHASE, SDO, and ASO-S. Additionally, the EUV images taken by the Solar Upper Transition Region Imager (SUTRI; Bai et al 2023) on board the first spacecraft of the Space Advanced Technology demonstration satellite series (SATech-01) of the Chinese Academy of Sciences (CAS) and the Solar X-ray and Extreme Ultraviolet Imager (X-EUVI) on board the FengYun-3E (FY-3E; Zhang et al 2022a) satellite, as well as the soft X-ray (SXR) 1-8 Å flux from GOES, were also employed. The details of these observations are summarized in Table 1.…”

Observation of Two Splitting Processes in a Partial Filament Eruption on the Sun: The Role of Breakout Reconnection

“…We also used observations from the Solar Upper Transition Region Imager (SUTRI) and the Chinese Hα Solar Explorer (CHASE) to analyze the dynamic evolution of an erupting filament and the accompanied blowout jet. SUTRI is a space-based EUV imager onboard the SATech-01 satellite launched by China in 2022 (Bai et al 2023). SUTRI uses the Ne VII 46.5 nm spectral line, which forms at a temperature of ∼0.5 MK, to image the upper transition region of the Sun (Tian 2017).…”

Internal Activities in a Solar Filament and Heating in Its Threads

“…The data were observed on 2022 November 1 from 16:50 UT to 17:15 UT with a target of AR 13135 by the spaceborne Atmospheric Imaging Assembly (AIA; Lemen et al 2012) et al 2022a;Zhang et al 2022), and the Solar Upper Transition Region Imager (SUTRI; Bai et al 2023;Wang et al 2023).…”